But you're wrong.
Article I, s. 10 is very clear.
Hey, thanks for pointing this out, Jim. Something I had overlooked. And, off topic, but AHA - here is where the South was explicitly forbidden from seceding from the Union: No State shall enter into any ...Confederation; ...emit Bills of Credit (click here to see Confederate notes), all, ironically, totally against the same Constitution that the South was so upset that it claimed the North wasn't following. Berry interesting!